Example embodiments of the inventive concepts relate to image sensors. More particularly, the inventive concepts relate to complementary metal-oxide-semiconductor (CMOS) image sensors with improved performance.
An image sensor is a semiconductor device that converts an optical image into electrical signals. Image sensors may be categorized as any one of charge coupled device (CCD) image sensors and CMOS image sensors (CIS). A CIS typically includes a plurality of two-dimensionally arranged pixels. Each of the pixels may include a photodiode that converts incident light into an electrical signal. CIS pixels may suffer from crosstalk, which occurs when light incident on one pixel affects the level of Tight detected at a different pixel. CIS pixels may also suffer from dark current, which can cause a pixel to register a value in the absence of incident light, and reset noise, which can cause a pixel to continue to register a value after the pixel has been reset.